chore: reinstall stable rust toolchain

[nadin-Starkware]

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[dorimedini-starkware]

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Dockerfile line 19 at r1 (raw file):

# Reinstalling the stable Rust toolchain to ensure a clean environment
RUN rustup toolchain uninstall stable-x86_64-unknown-linux-gnu && rustup toolchain install stable-x86_64-unknown-linux-gnu

why is this clean install needed...? isn't it deterministic? are there versions of this toolchain?

Code quote:

# Reinstalling the stable Rust toolchain to ensure a clean environment
RUN rustup toolchain uninstall stable-x86_64-unknown-linux-gnu && rustup toolchain install stable-x86_64-unknown-linux-gnu